1. Field of the Invention
This invention pertains generally to musical instruments, and more particularly to an apparatus and method for regulating the time for a piano key to return to rest after the key has been depressed.
2. Description of the Background Art
Automatic playing piano systems utilize actuator units, such as solenoids, to sequentially rotate the piano keys for reproducing a musical performance. A problem encountered with such automatic playing piano systems is the creation of mechanical noise from each key's action mechanism returning to its rest position after being actuated by the solenoid to strike a piano string. Such mechanical noise is apparent in all piano action mechanisms. This problem becomes more evident especially when the musical performance is played at low volumes, as opposed to higher volumes where the sounds produced by the strings help mask the mechanical noise from the piano action.
A known method to reduce and/or eliminate the mechanical noise is to reduce the rate of return of the action mechanisms to their respective rest positions. One method in particular employs a three step constant deceleration to silence the noise created by the action mechanism on electronic keyboards by applying a force to the solenoid actuator corresponding to the key's action mechanism to slow the mechanism's return to its rest position. This method presents problems in faithfully reproducing a piano performance. Because of the constant deceleration of the action mechanism, its return time is dramatically slowed. For example, a grand piano with an "unbraked" return time of approximately 35 milliseconds will have a "braked" return time of approximately 55 milliseconds. Trills (quick repetition of key strikes) will be missed because the obtainable repetition rate is reduced. Moreover, undesirable double hits of the string can easily occur due to the increased braking force caused by the solenoid actuators.
Accordingly, there exists a need for a method to regulate the return rate for a piano key's action mechanism, which maximizes the return rate and decreases the braking force required to regulate the return rate. The present invention satisfies these needs, as well as others, and generally overcomes the deficiencies found in the background art.